[programjames]

This is so confusing. If you create bigger roads, it usually doesn't solve the issue, as:

1) More people start to use the road, which can actually increase total commute time (Braess's paradox).

2) It removes room for the actual city. The city becomes more spread out, and people have to travel farther to get to their destinations!

Think about this: do you want to be encouraging other people to create more traffic along your commute? No way! You want everyone else off your roads, somehow get them to start biking or take the subway. And the best way to do that is to replace a couple lanes with bus/bike/streetcar lanes.